The in vitro activities of 39 antimicrobial agents against 23 isolates of Treponema hyodysenteriae, the majority of which were field isolates, were determined by the agar dilution technique. Quinoxalines, pleuromutilin, nitroimidazoles, and nitrofuran were the most active. Their activities ranged from </=0.10 to 1.56 mug/ml. Lincomycin, penicillins, chloramphenicol, tetracyclines, cephalosporin...
